ear

ear

[ēr]

the organ of hearing and equilibrium. (See Plates.) It is made up of the outer (external) ear, the middle ear, and the inner (internal) ear.

The outer ear consists of the auricle or pinna and the external acoustic meatus. The auricle collects sound waves and directs them to the external acoustic meatus; from there the waves travel through the external auditory canal to the eardrum (tympanic membrane).

The middle ear is separated from the outer ear by the eardrum. It contains the three ossicles, the malleus (hammer), incus (anvil), and stapes (stirrup), so called because of their resemblance to these objects. These three small bones form a chain across the middle ear from the eardrum to the oval window. The stapes causes a membrane in the oval window to vibrate, and the vibrations are transmitted to the inner ear. The middle ear is connected to the nasopharynx by the eustachian tube, through which the air pressure in the middle ear is equalized with the air pressure in the nose and throat. The middle ear is also connected with the cells in the mastoid bone just behind the outer ear. Two muscles attached to the ossicles contract when loud noises strike the tympanic membrane, limiting its vibration and thus protecting it and the inner ear from damage.

When a sound strikes the ear it causes the tympanic membrane to vibrate. The ossicles function as levers, amplifying the motion of the tympanic membrane, and passing the vibrations on to the cochlea. From there the vestibulocochlear (eighth cranial) nerve transmits the vibrations, translated into nerve impulses, to the auditory center in the brain.

Diseases of the Ear. Infections and inflammations of the ear include otomycosis, a fungal infection of the outer ear; otitis media, infection of the middle ear; and mastoiditis, an infection of the mastoid cells. deafness may result from infection or from other causes such as old age, injury to the ear, hereditary factors, or conditions such as otosclerosis. Disorders of equilibrium may be caused by imperfect functioning of the semicircular canals or from labyrinthitis, an inflammation of the inner ear. Menière's disease, believed to result from dilatation of the lymphatic channels in the cochlea, may also cause disturbances in balance.

Surgery of the Ear. Surgical procedures on the ear usually are indicated for chronic infection or hearing loss. An exception is myringotomy, incision of the tympanic membrane, which is sometimes necessary to relieve pressure behind the eardrum and allow for drainage from an inflammatory process in the middle ear. Surgical procedures involving plastic reconstruction of the small bones of the middle ear are extremely delicate and have been made possible by the development of special instruments and technical equipment. stapedectomy and tympanoplasty are examples of this type of surgery, which has done much to preserve hearing that would otherwise be lost as a result of infectious destruction or sclerosis. Inner ear implants are now being performed to improve hearing in patients who have severe sensorineural hearing loss. Other surgical techniques for sensorineural hearing loss are in the developmental stage.

Patient Care. Care following surgery of the ear is aimed at preventing infection and promoting the comfort of the patient. Since the ear is so close to the brain, it is extremely important to avoid introducing pathogenic organisms into the operative site. The external ear and surrounding skin must be kept scrupulously clean. If the patient's hair is long it should be braided or arranged so that it does not come in contact with the patient's ear and side of the face. Aseptic technique must be used in all procedures carried out immediately before and after surgery.

The patient should be instructed to avoid nose blowing, especially after surgery, when there is a possibility that such an action can alter pressure within the ear. Observation of the patient after surgery of the ear includes assessing function of the facial nerve; evidence of dysfunction could include inability to wrinkle the forehead, close the eyes, pucker the lips, or bare the teeth. Any sign of facial nerve damage should be reported to the surgeon. vertigo is another common occurrence after surgery of the ear; it is usually only temporary and will subside as the operative site heals. The patient with vertigo requires special protective measures such as side rails and support when out of bed, so as to avoid falls or other accidental injuries.

Most surgeons prefer that the dressings around the ear not be changed during the immediate postoperative period. Should excessive drainage require more dressings, these can be applied over the basic dressing. Any drainage should be noted and recorded, with excessive drainage reported immediately to the surgeon. (See also care of the patient with hearing loss.)

Anatomical features of the external ear. From Ignatavicius and Workman, 2002.

Structures of the middle ear.

beach earotitis externa caused by irritation from ocean water and other beach conditions.

cauliflower ear a thickened and deformed ear caused by accumulation of fluid and blood clots in the tissue after repeated injury; it is most often seen in boxers, for whom it is almost an occupational hazard. The ear will not recover its normal shape but can be restored to normal by plastic surgery.

ear

(ēr), [TA]

The organ of hearing and equilibrium, composed of the external ear, consisting of the auricle, external acoustic meatus, and tympanic membrane; the middle ear, or tympanic cavity, with its auditory ossicles and associated muscles; and the internal ear, vestibulocochlear organ, which includes the bony labyrinth (of semicircular canals, vestibule, and cochlea), vestibular and cochlear labyrinths.See also: auricle.

ear

a. The vertebrate organ of hearing, responsible for maintaining equilibrium as well as sensing sound and divided in mammals into the external ear, the middle ear, and the inner ear.

b. The part of this organ that is externally visible.

2. An invertebrate organ analogous to the mammalian ear.

3. The sense of hearing: a sound that grates on the ear.

ear′less adj.

ear

Etymology: AS, eare

one of two organs of hearing and balance, consisting of the external, middle, and internal ear. The external ear includes the skin-covered cartilaginous auricle visible on either side of the head and the part of the external auditory canal outside the skull. Together they form a funnel that directs sound waves toward the eardrum, or tympanic membrane, which marks the boundary between the external ear and the air-filled middle ear. The middle ear contains three very small bones, the malleus, incus, and stapes, which transmit vibrations caused by sound waves reaching the tympanic membrane to the oval window of the inner ear. The leverage of the ossicles, or middle-ear bones, increases the intensity of sound vibrations by more than 25 dB. Because the inner ear is filled with fluid, the increased intensity helps compensate for the loss of signal normally caused by sound-wave reflection of the fluid. The inner ear contains two separate organs: the vestibular apparatus, which provides the sense of balance, and the cochlea, with the organ of Corti, which receives vibrations from the middle ear and translates them into nerve impulses, which are again interpreted by brain cells as specific sounds.

Structures of the ear

ear

Physical exam The auditory apparatus, which is divided into the external ear–a conical tube that collects sound that vibrates the tympanic membrane–the outer barrier of the middle ear, which contains the ossicles–malleus, incus, and stapes, that mechanically amplify the sound transmitted at the oval window to the cochlea; the cochlea's neuroepithelial hair cells convert the mechanical signal into an electrical/neural signal that is identified by the brain as sounds, speech, music, etc. See Blue ear, Cauliflower ear, Inner ear, Lop ear, Malrotated ear, Middle ear, Mozart ear, Outer ear, Outstanding ear, Satyr ear, Swimmer's ear, Third ear.

EAR

Abbreviation for estimated average requirement.

ear

(ēr) [TA]

The organ of hearing: composed of the external ear, which includes the auricle and the external acoustic, or auditory, meatus; the middle ear, or the tympanic cavity with its ossicles; and the internal ear or inner ear, or labyrinth, which includes the semicircular canals, vestibule, and cochlea. See also: auricle Synonym(s): auris [TA] .

ear

(er)

STRUCTURE OF THE EAR

The organ of hearing and equilibrium. It consists of outer, middle, and inner portions, and is innervated by the eighth cranial nerve. See: illustration

The pathway of hearing is as follows: the auricle funnels sound waves from the environment through the external auditory canal to the tympanic membrane, which makes this thin epithelial structure vibrate. The vibrations are transmitted to the auditory ossicles and then to the perilymph and endolymph. The receptors are part of the organ of Corti and generate impulses transmitted by the cochlear branch of the eighth cranial nerve to the spiral ganglion and auditory tracts of the brain. The auditory areas are in the temporal lobes.

The healthy human ear responds to a variety of sounds, with frequencies ranging from about 20 to 20,000 Hz. It is most sensitive, however, to sounds whose frequencies fall in the 1500- to 3000-Hz range, the frequency range of most human speech. See: hearing

The receptors for equilibrium are in the utricle, saccule, and semicircular ducts, which are innervated by the vestibular branch of the eighth cranial nerve. Impulses from the utricle and saccule provide information about the position of the head, those from the semicircular ducts about the speed and direction of three-dimensional movement.

darwinian ear

external ear

The portion of the ear consisting of the auricle and external auditory canal, and separated from the middle ear by the tympanic membrane or eardrum. Synonym: auris externa; outer ear

foreign bodies in ear

Objects that enter the ear accidentally or are inserted deliberately. These are usually insects, pebbles, beans or peas, cotton swabs, or coins.

Symptoms

Foreign objects cause pain, ringing, or buzzing in the ear. A live insect usually causes a noise.

Treatment

Water must not introduced if any vegetable matter is in the ear because the water may push the foreign body further into the ear or cause the matter to swell and become firmly embedded.

To remove insects from the ear, a few drops of lidocaine should be instilled. Inorganic foreign bodies can be removed with small forceps by a health care provider.

glue ear

The chronic accumulation of a viscous exudate in the middle ear, occurring mostly in children between 5 and 8. It causes deafness, which can be treated by removal of the exudate.

STRUCTURE OF THE INNER EAR

inner ear

The portion of the ear consisting of the cochlea, the vestibule, and the bony semicircular canals, which contain the receptors for static and dynamic equilibrium. The receptors are innervated by the vestibulocochlear nerve. Synonym: auris interna; Internal ear

See: illustration

internal ear

lop ear

A cosmetic deformity of the earlobe in which the upper portion of the earlobe bows out laterally from the head.

middle ear

The air-filled expansion of the auditory tube separating the external auditory canal from the inner ear. Sound is transmitted through the middle ear as vibrations along a chain of three tiny bones, the auditory ossicles.

Mozart ear

nerve supply of ear

External: The branches of the facial, vagus, and mandibular nerves and the nerves from the cervical plexus. Middle: The tympanic plexus and the branches of the mandibular, vagus, and facial nerves. Internal:The vestibulocochlear nerve (eighth cranial).

outer ear

pierced ear

An earlobe that has been pierced with a needle so that a permanent channel will remain, permitting the wearing of an earring attached to the ear by a connector that passes through the channel.

surfer's ear

The formation of an exostosis in the external auditory canal of surfers, esp. those who habitually surf in colder waters.

swimmer's ear

A type of external otitis seen in swimmers, usually during the summer. It is typically caused by Staphylococcus aureus or Pseudomonas aeruginosa and is treated with a suspension of neomycin, polymyxin B sulfate, and hydrocortisone.

Fig. 139 Ear . The human ear.

ear

the sense organ of vertebrates concerned with reception of sound (hearing), BALANCE (detecting position with respect to gravity) and acceleration. The external ear is absent in amphibia and some reptiles, where the eardrum (tympanum) is at the skin surface; in other forms the external ear consists of an AUDITORY CANAL and the pinna, a projection of skin and cartilage. The middle ear or tympanic cavity (not present in some amphibians and some reptiles) lies between the ear drum and the auditory capsule. The EUSTACHIAN TUBE connects the middle ear to the pharynx; it contains the ear ossicles and lies within the bulla which is a projection of the skull. The inner ear or membranous labyrinth is contained in the auditory capsule; the utricle gives rise to the semicircular canals (for balance), and from the saccule the hearing organ arises in the form of the COCHLEA in some tetrapods.

Hearing results from sound waves striking the tympanic membrane and causing it to vibrate. The vibrations are transmitted to the oval window by means of a lever system operating between the three ear ossicles which magnify them. This disturbs the fluid in the vestibular canal of the cochlea and causes movement in REISSNER'S MEMBRANE, which then results in the fluid of the middle canal being displaced. This moves the basilar membrane and then disturbs the fluid in the tympanic canal which stretches the membrane covering the round window. Movement of the basilar membrane stimulates the organ of Corti (see COCHLEA and impulses are fired in the auditory nerve. Loud sounds cause greater movement of the basilar membrane and a higher frequency of impulses from the organ of Corti. Pitch of a sound determines the frequency of movement of the basilar membrane.

The ear.

ear

the structures concerned with hearing and also with balance and posture. (1) The external ear leads to the tympanic membrane (eardrum) which separates it from (2) the middle ear, where the chain of 'ossicles' transmits sound vibrations to (3) the inner ear containing the sense organs for hearing (the cochlea) and for movements of the head (the vestibular apparatus). Afferents from these pass into the brain in the auditory nerve . The cavity of the middle ear is connected to the pharynx via the Eustachian tube.

EAR

estimated average requirement

EAR

Abbreviation for estimated average requirement.

ear

(ēr) [TA]

Organ of hearing and equilibrium, composed of external ear,, consisting of auricle, external acoustic meatus, and tympanic membrane; middle ear,, or tympanic cavity, with its auditory ossicles and associated muscles; and internal ear,, the vestibulocochlear organ, which includes the bony labyrinth (of semicircular canals, vestibule, and cochlea), and vestibular and cochlear labyrinths. Synonym(s): auris.

ear

the organ of hearing and of equilibrium. The ear is made up of the outer (external) ear, the middle ear and the inner (internal) ear. The anatomical parts of all three can be found under their specific names. See also auricular, auditory, external ear.

The outer ear consists of the auricle, or pinna, and the external acoustic meatus. The auricle collects sound waves and directs them to the external acoustic meatus which conducts them to the tympanum.

The tympanic membrane (eardrum) separates the outer ear from the middle ear. In the middle ear are the three ossicles, the malleus (hammer), incus (anvil), and stapes (stirrup), so called because of their resemblance to these objects. These three small bones form a chain across the middle ear from the tympanum to the oval window of the inner ear. The middle ear is connected to the nasopharynx by the auditory tube, through which the air pressure on the inner side of the eardrum is equalized with the air pressure on its outside surface. Two muscles attached to the ossicles contract when loud noises strike the tympanic membrane, limiting its vibration and thus protecting it and the inner ear from damage.

In the inner ear (or labyrinth) is the cochlea, containing the nerves that transmit the electrical impulses stimulated by sound to the brain. The inner ear also contains the semicircular canals, which are essential for the sense of balance. When a sound strikes the ear it causes the tympanic membrane to vibrate. The ossicles function as levers, gearing down the motion of the tympanic membrane, and passing the vibrations on to the cochlea. From there the vestibulocochlear (eighth cranial) nerve transmits the vibrations, translated into nerve impulses, to the auditory center in the brain. See also hearing.

an erect, broad-based ear in dogs; seen in the French bulldog and Welsh corgi.

bear ear

one with a very rounded tip.

break in ear

the fold line in the semi-dropped ear of dogs.

broken ear

deformed or misshapen ears, as a result of injury or congenital defect. Most often of concern in dog breeds that are supposed to have erect or specifically defined ear conformation, e.g. Collie, German shepherd dog, Chihuahua.

button ear

in dogs, an ear flap lying close to the head, and pointing toward the eye. Seen in fox terriers.

ear cancer

a squamous cell carcinoma of the ear of sheep. The lesion commences around the free edge and then invades the entire ear.

ear canker

a lay term applied generally to otitis externa but sometimes specifically to that caused by ear mites.

ear carriage

drooped, erect, alert, all indicative of mental state or state of muscle tone. Also a specified feature of breed standards for dogs.

a misplaced tooth germ or ear tooth in horses; occur unilaterally at the base of the ear, attached to the temporal bone. Called also heterotopic polyodontia.

drop ear

an ear that is normally not erect; the end folds over or droops forward. Seen in many dog breeds.

drooping ear

inability of the ear to remain in an upright position in those species in which that is the norm. It may be a congenital abnormality, due to injury that has damaged the cartilage, or a sign of neurological deficit.

crusts, scabs and sometimes ulcerations, may occur at the edges of the external ear flap in dogs. Usually a form of seborrhea.

ear mark

patterned pieces of cartilage punched out as a means of identification. Very popular at one time with intricate codes to identify age and family groups of pigs. Marks nicked out of the edges but also the centers of the ears.

hypertrophic dermatitis appearing as small (0.5 inch diameter) plaques on the inner surface of the ear pinna in horses. They are scaly, slightly papillomatous, painless and alopecic. The cause is unknown.

result of phlebitis and venous thrombosis occurring in many septicemias. It is most common in pigs where it begins as purple discoloration of the ears and surrounding skin. Also part of the response in peripheral gangrene syndrome caused by ingestion of the fungus clavicepspurpurea.

a vice occurring in penned pigs and calves caused by boredom. Has no serious effect unless it leads to cannibalism in pigs.

ear tag

a technique of animal identification favored in sheep and cattle. Has the disadvantage that tags are often lost. This can be avoided by putting duplicates in each ear. The need to catch the animal to read the tag is overcome by using large placard type tags. For cattle being worked through a chute, tail tags are more convenient. Insecticides can be incorporated into the tag to provide protection against horn fly and head fly. May contain transponders for individual identification or trace back.

clipping off the tip of the external ear so that the animal can be identified from a distance. Limited categories available.

ear tip necrosis

a common problem in individual pig herds; sporadic cases usually related to frostbite, thrombosis after septicemic disease, especially Salmonella dublin in young calves; herd problems may be due to ergot poisoning or endophyte-containing hay, or an ear-sucking habit.

Patient discussion about ear

Q. Tinnitus (Ringing and Other Ear Noise) Anybody have this problem?
Urrrrrrrrrrr, I think I want to shoot myself,you know what I mean.
It is worst than the chinese torture.
Someone, please send me a good tip how to stop it.
I have this for 4 yrs and it is driving me crazy.
You cannot enjoy total complete silence.
They say silence is golden but not when you have this ringgi in your ears.
It gets worst when there is no noise.
The only remedy I have is eating hot spicy curry, it helps for 2-3 wks and then it comes back again and then eating spicy food again.
Listening to classical music helps to.
Oh well.....just have to suck it up.

A. I've read that lipoflavinoids can help.

Q. What causes high pitch ringing in one ear?

A. I never knew that about Iron. Thank you F3_4u

Q. my ears do not hear well especially when it's cold. i hear my breath and heart beat. what's my prolem? Denis when i breathe it feels like the breath goes through the ear when the weather is cold or when i do some excercise like jogging

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